\(\left(7^x-11^3\right)=2^5.2^2+200\)
BT2: Tính nhanh
15) \(1000-\left\{\left(-5\right)^3.\left(-2\right)^3-11.\left[7^2-5.2^3+8.\left(11^2-121\right)\right]\right\}\)
\(1000-\left\{\left(-5\right)^3.\left(-2\right)^3-11.[7^2-5.2^3+8.\left(11^2-121\right)]\right\}\)
=\(1000-\left\{[\left(-5\right).\left(-2\right)]^3-11.[7^2-5.2^3+2^3.\left(11^2-11^2\right)]\right\}\)
= \(1000-\left\{1000-11.[7^2-2^3.\left(5+0\right)]\right\}\)
= \(1000-[1000-11.\left(7^2-2^3.5\right)\)
= \(1000-[1000-11.\left(49-40\right)]\)
= \(1000-\left(1000-11.9\right)\)
= \(1000-\left(1000-99\right)=1000-1000+99\)
= 0 + 99 = 99
tính nhanh:
a) \(A=1500-\left\{5^3.2^3-11.\left[7^2-5.2^3+8\left(11^2-121\right)\right]\right\}\)
\(A=1500-\left\{5^3.2^3-11.\left[7^2-5.2^3+8\left(11^2-121\right)\right]\right\}\)
\(A=1500-\left\{125.8-11.\left[49-5.8+8\left(121-121\right)\right]\right\}\)
\(A=1500-\left\{1000-11\left[49-40+8.0\right]\right\}\)
\(A=1500-\left\{1000-11.9\right\}\)
\(A=1500-\left\{1000-99\right\}\)
\(A=1500-901=599\)
Tính :
A=-1500 - { \(^{5^3.2^3-11.\left[7^2-5.2^3+8.\left(11^2-121\right)\right]}\)} . (-2)
Ta tính các số mũ thành số hết
\(A=-1500-\left\{125.8-11.\left[49-40+8\left(121-121\right)\right]\right\}.2\)
\(A=-1500-\left\{1000-11.\left(9+0\right)\right\}.2\)
\(A=-1500-\left(1000-99\right).2\)
\(A=-1500-901.2\)
\(A=-1500-1802=-3302\)
A = \(10^3-\left\{-5^3.2^3-11.\left[x^2-5.2^3+\left(121-11^2\right)\right]\right\}\)
Tính A
\(A=10^3-\left\{-5^3.2^3-11.\left[x^2-5.2^3+\left(121-11^2\right)\right]\right\}\)
\(A=10^3-\left\{\left(-10\right)^3-11.\left[x^2-40\right]\right\}\)
\(A=10^3-\left\{\left(-10\right)^3-11x^2+440\right\}\)
\(A=10^3+10^3+11x^2-440\)
\(A=2000-440+11x^2\)
\(A=1560+11x^2\)
a)\(\left(x-1\right)^3=125\)
b)\(\left(2.x+1\right)^3=343\)
c)\(\left(7.x-11\right)^3=2^5.5^2+200\)
a, \(\left(x-1\right)^3=125\)
\(\Rightarrow x-1=5\Rightarrow x=6\)
b, \(\left(2x+1\right)^3=343\)
\(\Rightarrow2x+1=7\Rightarrow x=3\)
c, \(\left(7x-11\right)^3=2^5.5^2+200\)
\(\Rightarrow\left(7x-11\right)^3=32.25+200\)
\(\Rightarrow\left(7x-11\right)^3=1000\)
\(\Rightarrow7x-11=10\Rightarrow x=3\)
Chúc bạn học tốt!!!
a) \(\left(x-1\right)^3=125\Leftrightarrow\left(x-1\right)^3=5^3\Rightarrow x-1=5\)
\(\Leftrightarrow x=6\) vậy \(x=6\)
b) \(\left(2x+1\right)^3=343\Leftrightarrow\left(2x+1\right)^3=7^3\Rightarrow2x+1=7\)
\(\Leftrightarrow2x=6\Leftrightarrow x=\dfrac{6}{2}=3\) vậy \(x=3\)
c) \(\left(7x-11\right)^3=2^5.5^2+200\Leftrightarrow\left(7x-11\right)^3=32.25+200\)
\(\Leftrightarrow\left(7x-11\right)^3=800+200=1000=10^3\Rightarrow7x-11=10\)
\(\Leftrightarrow7x=21\Leftrightarrow x=\dfrac{21}{7}=3\) vậy \(x=3\)
\(\left(x-1\right)^3=125\)
\(\Rightarrow\left(x-1\right)^3=5^3\)
\(\Rightarrow x-1=5\)
\(\Rightarrow x=6\)
\(\left(2x+1\right)^3=343\)
\(\Rightarrow\left(2x+1\right)^3=7^3\)
\(\Rightarrow2x+1=7\)
\(\Rightarrow2x=6\)
\(\Rightarrow x=3\)
\(\left(7x-11\right)^3=2^5.5^2+200\)
\(\Rightarrow\left(7x-11\right)^3=32.25+200\)
\(\Rightarrow\left(7x-11\right)^3=1000\)
\(\Rightarrow\left(7x-11\right)^3=10^3\)
\(\Rightarrow7x-11=10\)
\(\Rightarrow7x=21\)
\(\Rightarrow x=3\)
\(\frac{9^{3.}7+27^2.3}{3^4.2+9^2.5^2}\)\(\frac{5.2^{11}.4^{11}-16^9}{\left(3.2^{17}\right)^2}\);\(\frac{\left(-3\right)^5.9^5.6^3.\left(-4\right)^4}{18^9}\);\(\frac{-2^4.5^2}{-8.9.119+36.78}\)
a)\(4.\left(\frac{1}{4}\right)^2+25.\left[\left(\frac{3}{4}\right)^3:\left(\frac{5}{4}\right)^3\right]:\left(\frac{3}{2}\right)^3\)
b)\(2^3+3.\left(\frac{1}{2}\right)^0+-1+\left[\left(-2\right)^2:\frac{1}{2}\right]-8\)
c) A=\(1000-\left\{\left(-5\right)^3.\left(-2\right)^3-11.\left[7^2-5.2^3+8\left(11^2-121\right)\right]\right\}\)
giúp mình với mọi người ơi
ai làm nhanh mà đúng đầu tiien mình tặng 3 tích
tim x
a) 2.\(3^x\) =162
b) \(\left(7\times x-11\right)^3=2^5\times5^2+200\)
c) \(\left(2\times x-15\right)^5=\left(2\times x-15\right)^3\)
a) 2.3x =162
3x =162:2
3x=81
3x=34
vậy x bằng 4
\(4^x+4^{x+3}=2160\)
\(2^{x-1}+5.2^{x-2}=\frac{7}{32}\)
\(\left(8-3x\right)^5=\left(8-3x\right)^3\)
\(\left(2x-3\right)^4=\left(2x-3\right)^6\)
\(4^x+4^{x+3}=2160\)
\(4^x\left(1+4^3\right)=2160\)
\(4^x\cdot65=2160\)
\(4^x=2160\text{ : }65\)
\(4^x=33,2307692\)
\(\Rightarrow\text{ Đề sai}\)
Bài giải
\(2^{x-1}+5\cdot2^{x-2}=\frac{7}{32}\)
\(2^{x-2}\left(2+5\cdot1\right)=\frac{7}{32}\)
\(2^{x-2}\cdot7=\frac{7}{32}\)
\(2^{x-2}=\frac{7}{32}\text{ : }7\)
\(2^{x-2}=32\)
\(2^{x-2}=2^5\)
\(\Rightarrow\text{ }x-2=5\)
\(x=5+2\)
\(x=7\)